If you do then be careful they don’t overcrowd the page and get in the way of real content. If they do then you may fall foul of a new Google algorithm change that tries to address the fact that most users find these ads quite annoying!
You can read the fulla rticle here http://www.seroundtable.com/google-page-layout-penalty-14612.html
and you can have alook at how google may see your website using this tool http://www.browsersize.googlelabs.com/
